1. Field of the Invention
The invention relates to a pumping unit, and more particularly to a crank-type non-beam pumping unit.
2. Description of the Related Art
Nowadays pumping units are widely used, and are divided into two types: a beam pumping unit, and a vertical pumping unit. The beam pumping unit features large number of components, complex structure, high production cost, low mechanical efficiency, and poor economy. As for the vertical pumping unit, there are several problems therewith: transportation thereof is inconvenient, and special equipments must be used to move it during workover operation; moreover, this type of pumping unit cannot meet requirement for coordinate installation of multiple pumping units among multiple oil wells.